This invention relates in general to control mechanisms and, in particular, to a control lever mechanism for controlling the operative position of the control valves of a hydraulic distributor.
More specifically, but without restriction to the particular use shown and described, this invention relates to a control lever mechanism to control the valves of a hydraulic distributor employed for the purpose of operating the gears of a transmission of a vehicle.
In the operation of a vehicle, such as, for example, an earth moving machine, the operator of the vehicle controls its operation through manipulation of a control lever which movement is coupled to valves of a hydraulic device to control the operation of the gears as required. Control of the valves of the hydraulic device is generally achieved through movement of a pivoted control lever in a multitude of directions relative to the vehicle. To facilitate operation of the machine, it is desirable that such control be effected by the use of a single lever. Control lever mechanisms employed in the prior art are deficient in providing a rigid, yet lightweight single lever linkage between the vehicle operator and the valves of the distributor because of the utilization of linkages and couplings subject to high friction losses. Because of this inefficient coupling of the movement of the control lever to control the valves, known devices subject the vehicle operator to burdensome physical effort during operation of the vehicle.
It is therefore an object of the invention to improve the control of valves of a hydraulic device;
A further object of this invention is to transmit movement from a pivoted control lever mechanism to two or more valves of a hydraulic device;
Another object of this invention is to reduce the friction generated in the couplings of the linkages of a control lever mechanism;
A still further object of this invention is to maximize the ease and effectiveness by which hydraulic valves of a hydraulic device are controlled.
These and other objects are attained in accordance with the present invention wherein there is provided a control lever mechanism for controlling the operative position of a plurality of control valves of a hydraulic distributor by coupling movement of a control lever into selected motion of a pair of rotatable output shafts controlling operation of the valves. Movement of the control lever in planes extending in a longitudinal, transverse, or combination of these directions, is transmitted to the output shaft through interconnecting linkages employing a plurality of spherical joints. The control lever mechanism also includes provisions to protect the linkages from being adversely affected by the introduction of foreign substances such as dirt and other elements.